mechatronics Flashcards
causal system
a system is causal if the output at time t does not depend on the values of the input at any time t’>t
memoryless system
a causal system is memoryless if the output at time t depends only on the input at time t. otherwise the system has memory
when is a system LINEAR
a system is linear when it is additive and homogenous
additive:
if adding the inputs results in the addition of individual outputs, the system is additive
x1(t)+x2(t) -> y1(t)+y2(t)
eg. y(t) = 2x(t)
x1(t) -> 2x1(t) = y1(t)
x2(t) -> 2x2(t) = y2(t)
x1(t)+x2(t) -> 2* (x1(t)+x2(t))
homogeneous:
scaling by a factor of c
what is the complementary function
the solution of the damped, free vibration equation. this tells us the transient motion that dies away as steady state vibration is achieved
what is the particular integral
tells us the steady state vibration at excitation frequency
this can be found by assuming a solution in the form: x = Xsin(omega*t-phi)
X-> vibration amplitude
phi-> phase angle
omega-> excitation frequency
rotating mass unbalance force equation:
F=mew^2 sin(wt)
amplitude=
mew^2
torsional system eq of motion
I theta: + c theta. + k theta = 0
damping frequency
wd = wn (1-damping coeff^2)